Edit, usando un poco Google, encuentro esto:
But you can decide to give one particular person access to your balance by providing this person a viewkey, a specific string. For the moment, support is limited to MyMonero.com-created addresses, since this wallet is the only one able to take advantage of viewkeys and MyMonero doesn't yet allow reading a non-MyMonero.com-created address (such as an address created with simplewallet). But later, support will be extended to any wallet and addresses.
Another optional transparency feature, hinted at in the original whitepaper but not implemented yet, is auditable addresses.
Finally, we have also considered other methods of allowing for transparency on specific transactions. People want to be able to selectively prove payments on demand and generally open up to transparency in a controlled manner, without everything being linkable and traceable to the rest of their transactions.
Gracias DonYo, estoy preguntando en varios sitios y todo ayuda